Method for assembling spring-biased hinge pin unit

ABSTRACT

A method for assembling a hinge pin unit of the type having a coil spring mounted on and surrounding one end margin of a hinge pin with one end of the spring being coupled to spring tension adjustment means at the end of the hinge pin and the opposite end of the spring being coupled to a first, rotatable extension on the hinge pin near a second extension fixed to the hinge pin. The two extensions are adapted to engage a pair of hinge leaves to bias the same in predetermined directions relative to each other. The method permits the assembly of the unit as the hinge pin is moved along a predetermined path.

United States Patent 1 Bitney 3,708,859 Jan. 9, 1973 METHOD FOR ASSEMBLING SPRING- BIASED HINGE PIN UNIT Robert H. Bltney, 10649 Morengo Drive, Cupertino, Calif. 95014 Filed: Feb. 16, 1971 Appl. No.: 115,517

lnventor:

References Cited UNITED STATES PATENTS Primary Examiner-Thomas H. Eager AttorneyTownsend and Townsend [57] ABSTRACT A method for assembling a hinge pin unit of the type having a coil spring mounted on and surrounding one end margin of a hinge pin with one end of the spring being coupled to spring tension adjustment means at the end of the hinge pin and the opposite end of the spring being coupled to a first, rotatable extension on the hinge pin near a second extension fixed to the hinge pin. The two extensions are adapted to engage a pair of hinge leaves to bias the same in predetermined directions relative to each other. The method permits the assembly of the unit as the hinge pin is moved along a predetermined path.

7 Claims, 3 Drawing Figures FIIGJ PATENTEDJAN 9197a 3,708,859

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ROBERT H. BITNEY ATTORNEYS PATENTEUJAH ems 3,708,859

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ROBERT H. BITNEY BY :1 J monuns METHOD FOR ASSEMBLING SPRING-BIASED HINGE PIN UNIT This invention relates to improvements in the manufaeture of hinge pins and, more particularly, to a method for assembling a hinge pin unit having springbias means thereon.

In US. Pat. No. 3,426,387, a spring-biased hinge pin unit is disclosed, the unit having a pair of relatively shiftable extensions coupled to a hinge pin or pintle with each extension adapted to engage a respective one of a pair of hinge butts which are interconnected by the hinge pin unit. A coil spring surrounding the hinge pin of the unit operates to bias one of the extensions in a predetermined direction relative to the other extension, the latter extension being rigid to the hinge pin itself. One end of the coil spring is coupled to the shiftable extension and the opposite end of the coil spring is coupled to tension adjustment means carried by the hinge pin. The coil spring surrounds one end portion of the hinge pin; thus, the overall assembly provides a compact, self-contained unit which requires only a minimum of operating space and is installed in substantially the same manner as a conventional hinge pin.

Since the hinge pin unit is comprised of a number of initially separate, interconnected parts, the construction of the hinge pin units lends itself to assembly of its parts in accordance with a predetermined sequence. Thus, the assembly can be made as the hinge pin itself travels along a preselected path during which time the various parts can be placed on the hinge pin and be coupled to it and to other parts.

The present invention provides a method for assembling the hinge pin unit of the aforesaid character as the hinge pin of the unit travels along a path past a number of assembly stations at each of which a respective part of the unit can become coupled to the hinge pin. The various parts are added in the proper sequence to the hinge pin while certain functions, such as welding, grinding, brushing and lubricating, are performed on various parts so that not only are the parts placed on the hinge pin, but also the parts are connected together and conditioned to cooperate with each other to form the finished unit. In this way, hinge pin units can be made in volume and in minimum time to minimize production costs while at the same time providing a quality product suitable for immediate use or for packaging for later merchandising.

The primary object of this invention is to provide a method for assembling a hinge pin unit of the type described wherein the various parts of the unit are coupled to the hinge pin thereof in accordance with a predetermined sequence and as the hinge pin of the unit passes a number of assembly stations to thereby minimize production time and costs.

Another object of this invention is to provide a method of the aforesaid character wherein the hinge pin ofa unit to be assembled is moved along a predetermined path while the various parts are added to it and as certain of the parts are interconnected and while certain functions are performed on various parts to condition the same and render the hinge pin unit ready for immediate use as soon as assembly thereof is complete.

Still another object of this invention is to provide an a method for assembling a hinge pin unit of the type disclosed in the aforesaid patent wherein the various parts are added one-by-one to the hinge pin as the same travels along a preselected path so that mass production techniques can be used in the assembly of a large number of hinge pin units to minimize production time and production costs.

Other objects of this invention will become apparent as the following specification progresses, reference being had to the accompanying drawings for an illustration of the hinge pin unit and the apparatus and method of this invention.

In the drawings:

FIG. 1 is an exploded view of the hinge pin unit which is assembled when carrying out the teachings of the present invention;

FIG. 2 is a side elevational view'of the hinge pin unit in an assembled condition, portions being in cross section to illustrate details of construction; and

FIG. 3 is a schematic side elevational view of the ap paratus for assembling a number of hinge pin units of the type described, showing a plurality of hinge pin units in various stages of assembly.

The hinge pin unit assembled in accordance with the teachings of this invention is denoted by the number 10 and is shown disassembled in FIG. I and assembled in FIG. 2. Unit 10 includes a hinge pin 22 having a circular head 24 rigidly secured to one end thereof. A rotatable member 26 having a tubular extension 27 rigid thereto is rotatably carried on pin 22 adjacent to and in abutment with one face of head 24. Member 26 has a number of spaced holes 28 therethrough near the outer periphery thereof, each hole 28 being movable into alignment with each of a number of holes 30 through head 24. For purposes ofillustration,,there are four holes 28 and five holes 30. When a hole 28 is aligned with a hole 30, a pin 32 can be inserted therethrough to thereby hold member 26 against rotation on pin 22.

Member 26 has a hole 36 in the lower face thereof for receiving one end 38 of a coil spring 40 which surrounds pin 22. The opposite end 42 of spring 40 is received within a hole 44 in a first washer-like member 46 rotatably mounted on pin 22. Member 46 has a leg 48 provided with a number of spaced teeth 50 on one longitudinal edge 52 thereof. Member 46 and its leg 48 define an extension for coupling spring 40 with a first hinge leaf. Member 46 has a tubular projection 53 surrounding pin 22 and extending axially thereof. Projection 53 prevents wobble of leg 48 with respect to pin 22 so that leg 48 remains substantially parallel with pin 22 at all times. Also, projection 53 substantially eliminates wear on pin 22 due to the rotation of member 46 relative thereto.

While head 24 and member 26 are shown as being provided with the holes therethrough for receiving pin 32, it is to be understood that these elements can be provided with edge notches or recesses rather than holes for this purpose.

A second washer-like member 54 is rigidly secured to hinge pin 22, such as by brazing or the like. A Teflon washer 55 is disposed between members 46 and 54 to permit the same to easily move relative to each other. Member 54 has a leg 62 provided with spaced teeth 64 on one longitudinal edge 66 thereof. Member 54 and leg 62 define an extension for coupling pin 22 to a second hinge leaf.

A tubular cap 68 is removably placed about spring 40 so as to conceal the same when hinge pin unit is in use. Cap 68 extends to the upper face of member 54 and is notched to clear the portion of member 46 which is interconnected with the upper end of leg 48.

The method of the present invention is carried out with the use of the apparatus shown in FIG. 3 which includes a conveyor 70 for receiving a plurality of hinge pins 22 and for moving the same along a predetermined path. For purposes of illustration, the conveyor is constructed to advance the hinge pin along a straight line and the conveyor itself may be of any suitable length. Also, it may move at any desired speed commensurate with the performance of the various tasks in assembling a plurality of hinge pin units 10. The drive means 72 coupled with conveyor 70 moves the same in the direction of arrow 74.

The conveyor may be of any suitable construction, such as a belt material provided with a plurality of holes 76 therethrough for receiving the hinge pins 22. The conveyor may be endless so that it can be used for substantially uninterrupted assembly of a large number of hinge pin units 10 in a given working day.

FIG. 3 illustrates an assembly line and the sequence in which the various parts of a hinge pin unit 10 are placed on and coupled to a particular hinge pin 22. Initially, each hinge pin is coupled to conveyor 70 at a first assembly station, such as by inserting it through a hole 76. The hinge pin will have previously been provided with member 54 thereon, the member being welded or otherwise rigidly secured to the hinge pin with leg 62 thereof generally parallel with the hinge pin. When inserted into a hole 76, the hinge pin will permit its leg 62 to be located relative to the conveyor such that the hinge pin remains substantially vertical as it transverses the assembly line by one stretch of the conveyor.

Hinge pin 22 is preferably automatically coupled with the conveyor by means (not shown) adjacent to the conveyor at the first assembly station. At each of the other assembly stations along the path of the conveyor, a parts feeder is preferably provided to direct or feed the respective parts onto the hinge pin so as to render the assembly of a number of hinge pin units substantially automatic to minimize production costs. As shown in block form in FIG. 3, several parts feeder 77, 79 and 81 are provided at the first three assembly stations, parts feeders at other stations being omitted for simplicity.

As the conveyor moves to the right when viewing FIG. 3, it passes a second assembly station at which a washer 55 is placed on the upper end of the hinge pin so that the washer drops onto the flat, upper surface of member 54. Continued movement of the conveyor causes the hinge pin to move past the third assembly station at which a member 46 is placed on the hinge pin. Member 46 gravitates to a location at which it is disposed on and engages the flat, upper surface of washer 55. Also, leg 48 of member 46 will be located relative to the conveyor such that it does not prevent hinge pin 22 from remaining in a substantially vertical position.

The conveyor then moves the hinge pin to a fourth assembly station at which a coil spring 40 is placed on the hinge pin above member 46. The lower end 42 of the spring is guided into hole 44 of member 46. At this station, the spring is uncompressed.

At a fifth assembly station, the hinge pin receives the member 26, the latter being mounted on the upper end of the hinge pin and being supported by the upper extremity of spring 40; Member 26 then passes beneath a lateral flange 78 of a fixed bar 80 above conveyor 70 at the next station. When this occurs, the lower end of the hinge pin engages the inclined upper surface 82 at one end ofa ramp 84. Flange 78 is constructed in a manner such that it allows the hinge pin to elevate with respect to the conveyor as member 26 remains beneath flange 78. This movement causes spring 40 to compress since members 46 and 54 move upwardly with the hinge pin. Also, this exposes a greater length of the upper end of the hinge pin so that, at the next assembly station, head 24 is placed on the upper end of the hinge pin above flange 78. Other means for causing compression of the spring can be used, if desired.

At the next station, head 24 is rigidly secured to the hinge pin in any suitable manner, such as by welding, staking or by screwing it on to the hinge pin. Preferably, this is accomplished by a welding process and arrow 86 (FIG. 3) represents the welding apparatus for this purpose. The welding can occur as the hinge pin commences to move downwardly along an inclined upper surface 87. at the opposite end of ramp 84 or it can occur when the lower end of the hinge pin engages a horizontal upper surface 85 of the ramp. As the hinge pin moves along surface 87, the compression of spring 40 is removed.

The unit is then moved past a grinding wheel 88 at the next assembly station at which the excess portion of the hinge pin is ground away from head 24. Also, wheel 88 polishes the junction between the hinge pin and head 24.

The unit then passes a wire brush 90 at the next station. The brush can be of any type, such as a revolving brush for cleaning the unit from all sides. The brush is shown above and at the side of the unit in FIG. 3; however, the brush could be located at other positions as well. Also, more then one brush can be used, if desired.

The hinge pin then moves past a side bar 92 at the next station, the bar having a flat side which engages one of the flat side faces of member 26 to prevent the member from rotating relative to the conveyor. Then, pin 22 is engaged by a rotary drive 94, shown schematically coupled with the hinge pin, to cause the same to rotate through a limited are about its axis as indicated by arrow 96. This movement causes head 24 to rotate relative to member 26 to align a pair of holes 28 and 30 in member 26 and head 24, respectively. Then, pin 32 is inserted in the aligned holes. With member 26 and head 24 interconnected by pin 32, legs 48 and 62 will be biased in specific directions relative to each other.

The unit is then moved past a washing station at which a cleaning liquid issuing from nozzles 98 under pressure washes the unit assembled thus far. Then the unit continues on to the next station at which a lubrication means 100 applies a lubricant, such as oil or the like, to the unit to lubricate the same. Cap 68 is then installed and finally the unit is complete and separated from the conveyor such as by lifting it out of the corresponding hole 76. The unit can then be individually packaged or stored along with a number of other such units in a carton for shipment in bulk form. No further processing of the unit is thereafter required inasmuch as it is now ready for use.

I claim:

1. A method for assembling a spring-biased hinge pin of the type having a pintle, a pair of relatively shiftable extensions on the pintle, a coil spring surrounding the pintle and coupled to one of the extensions, and a pair of relatively rotatable members defining parts of a spring tensioning means comprising: moving the pintle with one extension rigidly secured thereto along a predetermined path with the pintle in a generally vertical position; placing the other extension on the pintle when the latter is at a first location along said path; placing a coil spring on the pintle and coupling one end of the spring to the other extension when the pintle is at a second location along said path; placing one of said members on the pintle and coupling the other end of the spring to the one member when the pintle is at a third location along said path; compressing said spring; placing the other member on the pintle above the one member when said spring is compressed and when the pintle is at a fourth location along said path; securing said other member to the pintle when the spring is compressed and when the pintle is at a fifth location along said path; removing the compression of the spring; and shifting the pintle out of said path.

2. A method as set forth in claim 1, wherein said step of compressing the spring includes elevating the pintle as said one member is held against vertical movement.

3. A method as set forth in claim 2, wherein said holding step includes moving the one member beneath a generally horizontal surface while permitting the pintle to move vertically relative to the surface.

4. A method as set forth in claim 2, wherein said elevating step includes moving the lower end of the pintle along an inclined surface.

5. A method as set forth in claim 1, wherein said securing step includes welding said other member to the pintle to permit the members to rotate relative to each other.

6. A method as set forth in claim 1, wherein is included the step of cleaning and lubricating the assembled unit after said other member has been secured to the pintle.

7. A method as set forth in claim 1, wherein is included the step of rotating the pintle and the other member relative to said path aboutthe axis of the pintle as the one member is held against rotation relative to the path to thereby tension the spring, and releasably coupling the one member to the other member after the spring has been tensioned. 

1. A method for assembling a spring-biased hinge pin of the type having a pintle, a pair of relatively shiftable extensions on the pintle, a coil spring surrounding the pintle and coupled to one of the extensions, and a pair of relatively rotatable members defining parts of a spring tensioning means comprising: moving the pintle with one extension rigidly secured thereto along a predetermined path with the pintle in a generally vertical position; placing the other extension on the pintle when the latter is at a first location along said path; placing a coil spring on the pintle and coupling one end of the spring to the other extension when the pintle is at a second location along said path; placing one of said members on the pintle and coupling the other end of the spring to the one member when the pintle is at a third location along said path; compressing said spring; placing the other member on the pintle above the one member when said spring is compressed and when the pintle is at a fourth location along said path; securing said other member to the pintle when the spring is compressed and when the pintle is at a fifth location along said path; removing the compression of the spring; and shifting the pintle out of said path.
 2. A method as set forth in claim 1, wherein said step of compressing the spring includes elevating the pintle as said one member is held against vertical movement.
 3. A method as set forth in claim 2, wherein said holding step includes moving the one member beneath a generally horizontal surface while permitting the pintle to move vertically relative to the surface.
 4. A method as set forth in claim 2, wherein said elevating step includes moving the lower end of the pintle along an inclined surface.
 5. A method as set forth in claim 1, wherein said securing step includes welding said other member to the pintle to permit the members to rotate relative to each other.
 6. A method as set forth in claim 1, wherein is included the step of cleaning and lubricating the assembled unit after said other member has been secured to the pintle.
 7. A method as set forth in claim 1, wherein is included the step of rotating the pintle and the other member relative to said path about the axis of the pintle as the one member is held against rotation relative to the path to thereby tension the spring, and releasably coupling the one member to the other member after the spring has been tensioned. 